Carpets, draperies, blinds, upholstery, solid surfaces, and the like are often cleaned using steam/hot water systems. Since these units typically operate on similar principles, but at different pressures and with different solvents, they are all generically and interchangeably referred to herein as carpet cleaners, carpet cleaning machines, systems, equipment, units, and so on. In general, steam/hot water systems include the same basic components, namely a wand for dispensing and recovering a cleaning fluid, an optional reservoir for holding reserve fluid, a fluid pump for providing pressurized cleaning fluid at the wand, an air pump (sometimes referred to as a vacuum pump) for sucking up spent fluid, and a spent fluid holding tank. Carpet cleaning equipment contemplated herein ranges from relatively small residential units to large, truck mounted units with long hoses reaching from the truck to the surface to be cleaned.
The efficacy of steam/hot water type carpet cleaning equipment is dependent upon many factors including operator skill and experience, the quality and condition of the machine, the solvents used, the temperature at which the cleaning fluid is dispensed, etc. However, there are four factors that affect both the efficacy of the carpet cleaning apparatus and the amount of dry time required to dry a recently cleaned carpet: fluid pressure, suction or liquid evacuation capabilities, temperature of the water or other solution used, and the amount of agitation provided. The pressure and the temperature of the solution used in traditional cleaning systems are somewhat limited due to established safety standards. More specifically, if the pressure and heat of the solution passing through the carpet cleaner exceed the containment capabilities of the carpet cleaning unit, undesirable accidents may occur.
Consequently, many carpet cleaning systems focus on enhancing the suction and agitation capabilities of the carpet cleaning systems in order to reduce the necessary dry time for the cleaned articles. Specifically, by enhancing the agitation capabilities of a carpet cleaning system, fewer passes entailing distribution of the cleaning solution may be used to provide adequate cleaning. Less cleaning solution equates to reduced drying time for the article being cleaned and increased income to an employer of the carpet cleaning system. Further, enhancing the vacuum capabilities of the carpet cleaning system will remove more cleaning solutions per pass, resulting in reduced dry times.
Traditional carpet cleaning systems prefer rotating brushes for agitating the carpet and spray nozzles for spraying cleaning solution onto the carpet. According to traditional embodiments, the solution dispensing components are located relatively remote from the vacuum recovery device, causing cleaning solution to penetrate deeply into the carpet prior to recovery and therefore degrading solution recovery effectiveness. Additionally, the use of brushes causes penetration of the carpet with flexible bristles and consequently pulls out carpet fibers and generally degrades the carpet and causes excessive wear. Further, the use of brushes to enhance agitation is relatively expensive and complex, causing brush agitating carpet cleaning systems to suffer from poor reliability. For example, rotating brushes are connected with belts and pulleys which are relatively expensive and a common source of maintenance problems.